An Experimental Evaluation Of Indirect Direct Evaporative Cooling Unit For Hot Climate

Direct and indirect evaporative cooling system is experimentally investigated using a plate heat exchanger for hot climate conditions. The effects of chilled water and ambient temperatures, water flow rates, humidity, and the operating cooling mode on the supply air temperature was investigated for three configurations. The system dry bulb and wet effectiveness was estimated for all conditions under consideration. It was found that the dry bulb effectiveness approached 17%, while it was in the range of 72-98% for the wet bulb effectiveness. In addition, the secondary air saturation effectiveness was calculated with varying water flow rates. It was found that the increase of water quantity in the heat exchanger would increase the refrigeration capacity and lead to a higher secondary air temperature difference. This resulted in higher saturation effectiveness for the system. These results were compared with available numerical data for calibration and validation purposes.